Dental lavatory



Oct. 26, 1937. BB. SWINNERTON I 2,097,167

DENTAL LAVA TORY Filed Nov. 25, 1936 2 Sheets-Sheet l INVENTOR 5; I BMEW 55 ZZWW W Patented Oct. 26, 1937 UNITED I sT 'rEs 2,097,167 DENTAL LAVATORY Bert B. Swinnerton, Tifl'in, Ohio, assignor to Standard Sanitary Manufacturing Company, acorporation of New Jersey 7 Application November 25, 1936, Serial No. 112,717

10 Claims.

My present invention relates to sanitary fixtures and more especially to dental lavatories and the like.

Dental lavatories of the usual types have been used for many years and have generally been entirely satisfactory in their normal operation. Under abnormal conditions, however, such lavatories have a serious disadvantage in that they become a source of contamination of the fresh water supply. When such lavatories become clogged, as not infrequently happens, the water level rises to the top of the lavatory and if the water supply valves are opened while a negative pressure exists in the water supply system backsiphonage of waste matter from the lavatory into the water supply system unavoidably occurs. The disadvantages and dangers connected with such back-siphonage will be obvious but insofar as I am aware no provision has heretofore been made which, will effectively and simply eliminate such back-siphonage.

It is accordingly one of the objects of my present invention to provide a dental lavatory which by its very construction will render back-siphonage into the fresh water supply impossible.

It isanother object of my invention to provide a dental lavatory with a special'wall structure .which simply, efiiciently and automatically prevents back-siphonage from the lavatory into the sources of freshwater supply.

A further object of my invention resides in making dental lavatories with an upstanding wall structure provided with a series of communicating chambers so constructed and arranged'that upon the arising of abnormal conditions in the lavatory and water supply system a vacuumbreaking effect will be produced which will positively prohibit back-siphonage.

Other and furtherobjects and. advantages of my present invention will either be understood .by those skilled in this art orv will be apparent or pointed out hereinafter.

In the accompanying drawings forming a part hereof:

Figure 1 is a plan view of a dental lavatory embodying my present invention;

Fig. 2 is a front elevational view of the lavatory of Fig. l;

Fig. 3 is a rear elevational view of my new lavatory with portions broken away to expose details thereof; and V Fig. 4'is a vertical sectional view taken on the line IV-IV of Fig. 2.

Like numerals designate corresponding parts throughout the several views of the drawings.

In general, my invention comprises-a dental or other'lavatory which is provided with an upstanding wall structure and wherein such wall structure is so cast or otherwise formed during the manufacture of the lavatory that a series of 5 communicating openings and a spout are formed therein. These openings are so disposed and. arranged: that when the water level in the lavatory rises beyond a certain point and when the water supply valves are opened while a negative pres- 10 sure exists in the water supply system, a venting will occur, thus breaking the vacuum or negative pressure in the water supply system and eliminating any possibility of back-siphonage from said lavatory to said water supply system. 15'

Referring now to the drawings indetail, the numeral It indicates a hollow rim which is pref erably but not necessarily made of vitreous china. The bore or cavity in the rim is designated by V the numeral II and a plurality of circumfer 20 entially spaced washdown openings l2 are provided in the inner under side of the rim, thus giving communication between the cavity l l in the rim and the bowl I3 -located below the rim.

The bowl [3 is likewise preferably made of vit- 25 v reous china or similar material and is of conventi-onal cup-shape; it isprovided in its bottom with a-plurality of drain openings indicated by the numeral M. I

Disposed beneath the said bowl I3 is the trap- 30 forming member I5 likewise preferably made of vitreous material and likewise being generally cup-shaped. The trap-forming member I5 is provided with an aperture [6 in its bottomfor the'reception of a drain plug indicated by the numeral l1. Projecting downwardly from said vitreous bowl I3 is the seal wall I8. This seal wall projects into the trap-forming member 15 forming a seal passage I9. A vitreous web 20 extends from the trap andforms one side of dischargeorifice 2|. Extending from said bowl is another vitreous web 22 which, with web 20, completes the formation of the discharge orifice as will be clearly apparent from Fig. 4 in particular.

Rising from said bowl and rim is the upstand- 45 ing vitreous wall structure 23 which terminates in a shelf top 24 as shown. This Wall structure is so'cast or formed during the manufacture of the lavatory that it is provided with a spout 25 and. a series of communicating chambers tobe 50 hereinafter described. A water inlet opening 26 is provided in a thickened portion2l of the wall structure 23 for the reception of a pipe fitting 28 ada'pt'ed 'for'connection" with an associated source of water supply. Chamber 29 is adapted to receive water from fitting 28 connected to the associated water supply system which is arranged to provide either hot or cold water to the lavatory or a mixture of hot and cold water and in the latter case chamber 29 also functions as a tempering or mixing chamber. This chamber 29 communicates with a second chamber 30 via the connecting apertures 3|. It will be noted from Fig. 3 that theupper portion .of chamber 30 is divided and is open to the atmosphere, thus providing vents which are indicated bythe numerals 32. Water received by chamber 30 from chamber 29 passes into the hollow rim cavity II and thence via washdown openings I2 to the bowl for flushing and cleaning purposes.

Hot and cold water supply valves 33 are pro-- vided as shown, each of which is suitably connected by piping 34 to a suitable source of water in supply duct 35. The valves are operated by valve stems 36 which are, in conventional manner, provided with operating handles 31 and the valve stems 36 are also provided with the usualescutcheons 38. From the valves 33 slip pipes 39 lead to water supply inlet 28 and connection is made at the rear of the wall structure 23- at the thickened portion thereof by means of a suitable expansion joint indicated by the numeral 69. A suitable waste or discharge pipe is suitably connected in the usual manner to discharge orifice 2| heretofore mentioned and such pipe leads to any suitable sewer or discharge duct. Numeral indicates a suitable connecting member for connection with such sewer or discharge duct.

N ormal operation In the normal operation of the dental lavatory the valves 33 are opened to the desired extent and this causes water to flow into chamber 29. Where-hot and cold water are both being utilized chamber 29 tempers or mixes the same and then divides the water into two paths or streams, one of which passes through the spout 25 and into the bowl of the lavatory and the other of which passes via openings 3|, chamber 30 and washdown openings I2 to the bowl I3 through the rim. Water drains into trapway I through drain openings I4 and thence to the discharge pipe, water normally standing in the'trap-way to the level shown in Fig. 4 for the usual purposes. 1

Abnormal operation gisnot infrequently happens in connection with dental or other lavatories, either the trapway, the drain openings or the washdown openings become clogged. In some cases also the sewer backs up or becomes clogged. In the event that any of these conditions arise water naturaldownopenings I2. It not infrequently happens also that a vacuum. or negative pressure temporarily existsin the water supply pipes and/or system which may be due to'a number of different factors. For example, repair work may be going on inconnection with the water supply system and water may be in process of being drained from thesystem. In other cases, sudden large demand upon .the water supply system, especially at a lower level than the lavatory, likewise causes a negative pressure to arise in the water supply system. If the valves 33 are opened when the'water level in the lavatory lies above the washdown openings and while a negative ,I3 $$l ,r ex ts in. the wa er. supply syst m, .in

said spout and to said rim. .ly rises in the lavatory until it covers the washr '3I; into chamber 29 and thence into water supply pipes where it breaks the vacuum. There- 'fore,'in'a lavatory constructed as herein described, such back-:siphonage from the lavatory into the water supply system is efiectively eliminated.- While a certain amount of air would, under the conditions named, be sucked in through spout 25, this in itself is insufiticient to effect the purposes of the present invention.

From the foregoing description taken in connection with the drawings, the construction and op'e'rationboth under normal and abnormal conditions of my present invention will be readily understood. I wish to point out, however, that the foregoing is intended more in an illustrative than in a limitative or restrictive senseand that so long as I adhere to the general principles and considerations above set forth, I may make certain variations, substitutions, alterations or omissions in the construction of any particular lavatory. While I have stated that the rim, bowl, trap-way and wall structure are preferably cast from vitreous china or. other vitreous or silicious material, it is within the principles and scope of my present invention to make these members of other materials such as suitablemetals. While I have shown the rim, bowl, trapway and wall structure as being unitary or integral, I am not restricted in this because it is within the purview of my invention to make the lavatory in as many parts as may be convenient or dictated by good judgment and experience and then to assemble the same into a complete unit. Rather, the scope of the invention is to be measured by the sub- -joined claims and all modifications indicated by the foregoing or'such as will be'understood or appreciated by those skilled in this art are considered by me as a part of my present invention.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent'is: r r i 1'. A lavatory comprising a' bowl having drain openings in its bottom, a trapway below said bowl and communicating with a waste outlet, a hollow rim superjacent said bowl and provided with circumierentially spaced washdown openings, a spout for supplying water to said bowl and means for irreversibly supplying water to 2. A lavato'rycomprising a bowl having drain openings in its bottom, a trapway below said bowl and communicating with a waste outlet, a hollow rim superjacent said bowl and provided with circumferentially spaced washdown openings, a spout; for supplying water to said bowl and means for irreversibly supplying water to 'said spout andto'. said rim, said means including a series of passageways interconnecting the water. supply means'with said rim, said spout and the atmosphere, whereby, irrespective of conditions in said lavatory and water-supply means,

.back-siphonage'from said lavatory to said water supply means is prevented.

3. A,lavatory comprising a bowl having drain onerlingsin its. bottom, a trapwaybelow said bowl conditions in the lavatory and water supply means.

4. A dental lavatory comprising a bowl having drain openings in its bottom, a trapway below said bowl and communicating with a waste outlet, a hollow rim superjacent said bowl and provided with circumferentially spaced washdown openings, a back wall rising from said rim and terminating in a shelf-top, a spout formed in said back wall, a chamber in said back'wall communicating with said spout and with said hollow rim, means for supplying water to said chamber and means for breaking vacuum arising in the water supply means and for preventing the same from causing back-siphonage from said lavatory.

5. In a dental lavatory of the type described, a wall structure provided with a chamber for receiving and distributing water and a second chamber communicating with the first chamber, the second chamber being vented to the atmosphere.

6. In a dental lavatory having a hollow rim provided with washdown openings communicating with a subjacent bowl, a wall structure having a spout and a series of communicating chambers formed therein, one of said chambers being adapted to receive and distribute water from an associated source of water supply and another of said chambers being vented to the atmosphere.

'7. In a. dental lavatory having a hollow rim provided with washdown openings communicating with a subjacent bowl, an upstanding Wall structure terminating in a shelf-top, said wall structure having a spout formed therein and being provided with a series of communicating chambers interconnecting the spout and the washdown openings with a source of water supply, one of said chambers being vented to the atmosphere, said wall structure, under normal conditions, distributing water to said spout and said washdown openings and, under abnormal conditions, preventing back-siphonage into said water supply. v

8. In a dental lavatory having a hollow rim provided with washdown openings communicating with a subjacent bowl, a wall structure having a spout and a series of communicating passageways formed therein, one of said passage- Ways being adapted to receive water from an associated source of water supply and to distribute it to said spout and to another of said passageways which latter is vented to the atmosphere and adapted to deliver water to said washdown openings.

9. A lavatory comprising a bowl having drain openings, a hollow rim on said bowl provided with circumferentially spaced washdown openings, a back wall rising from said rim, a spout formed in said back wall, means for supplying Water to said spout and to said washdown open.- ings and means operative under all conditions for preventing back siphonage from said lavatory to said water supply means.

10. A lavatory comprising a bowl having drain openings in its bottom, a trapway below the bowl communicating with a waste outlet, a hollow rim on the bowl provided with circumferentially spaced washdown openings on its under side, a back wall rising from said rim and means operatively associated with said back wall to supply water to said bowl and said washdown openings and to prevent back siphonage of such water irrespective of conditions encountered in the use of the lavatory.

BERT B. SWINNERTON. 

